NHTSA Interpretation File Search
Overview
NHTSA's Chief Counsel interprets the statutes that the agency administers and the standards and regulations that it issues. Members of the public may submit requests for interpretation, and the Chief Counsel will respond with a letter of interpretation. These interpretation letters look at the particular facts presented in the question and explain the agency’s opinion on how the law applies given those facts. These letters of interpretation are guidance documents. They do not have the force and effect of law and are not meant to bind the public in any way. They are intended only to provide information to the public regarding existing requirements under the law or agency policies.
Understanding NHTSA’s Online Interpretation Files
NHTSA makes its letters of interpretation available to the public on this webpage.
An interpretation letter represents the opinion of the Chief Counsel based on the facts of individual cases at the time the letter was written. While these letters may be helpful in determining how the agency might answer a question that another person has if that question is similar to a previously considered question, do not assume that a prior interpretation will necessarily apply to your situation.
- Your facts may be sufficiently different from those presented in prior interpretations, such that the agency's answer to you might be different from the answer in the prior interpretation letter;
- Your situation may be completely new to the agency and not addressed in an existing interpretation letter;
- The agency's safety standards or regulations may have changed since the prior interpretation letter was written so that the agency's prior interpretation no longer applies; or
- Some combination of the above, or other, factors.
Searching NHTSA’s Online Interpretation Files
Before beginning a search, it’s important to understand how this online search works. Below we provide some examples of searches you can run. In some cases, the search results may include words similar to what you searched because it utilizes a fuzzy search algorithm.
Single word search
Example: car
Result: Any document containing that word.
Multiple word search
Example: car seat requirements
Result: Any document containing any of these words.
Connector word search
Example: car AND seat AND requirements
Result: Any document containing all of these words.
Note: Search operators such as AND or OR must be in all capital letters.
Phrase in double quotes
Example: "headlamp function"
Result: Any document with that phrase.
Conjunctive search
Example: functionally AND minima
Result: Any document with both of those words.
Wildcard
Example: headl*
Result: Any document with a word beginning with those letters (e.g., headlamp, headlight, headlamps).
Example: no*compl*
Result: Any document beginning with the letters “no” followed by the letters “compl” (e.g., noncompliance, non-complying).
Not
Example: headlamp NOT crash
Result: Any document containing the word “headlamp” and not the word “crash.”
Complex searches
You can combine search operators to write more targeted searches.
Note: The database does not currently support phrase searches with wildcards (e.g., “make* inoperative”).
Example: Headl* AND (supplement* OR auxiliary OR impair*)
Result: Any document containing words that are variants of “headlamp” (headlamp, headlights, etc.) and also containing a variant of “supplement” (supplement, supplemental, etc.) or “impair” (impair, impairment, etc.) or the word “auxiliary.”
Search Tool
NHTSA's Interpretation Files Search
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ID: aiam3233OpenMr. Dick Pilch, P.O. Box 1311, Puyallup, Washington 98371; Mr. Dick Pilch P.O. Box 1311 Puyallup Washington 98371; Dear Mr. Pilch: This responds to your February 7, 1980 letter to the Department o Transportation, in which you complained about the failure of a tire on your truck. Specifically, you stated that the tires on the front axle of your truck were overloaded by 570 pounds each, and that no non-radial tire is currently manufactured which would not have been overloaded if used on this front axle.; If the tires which were overloaded came as original equipment on th truck, the manufacturer of the truck violated Federal Motor Vehicle Safety Standard No. 120 (49 CFR 571.120). Paragraph S5.1.2 of Standard No. 120 requires the sum of the maximum load ratings of the tires fitted to any axle to be at least equal to the gross axle weight rating of that particular axle. This requirement is applicable to all trucks manufactured on or after September 1, 1976. If your truck was manufactured after that date, please send ne the name of the manufacturer as well as the information provided by the manufacturer specifying the appropriate tire sizes to be used on the truck. The information concerning appropriate tire sizes will appear on a label on the door latch post on the driver's side of the truck. If the manufacturer has violated Standard No. 120, appropriate steps will be taken by the agency.; You also stated that certain radial tires would have met th load-carrying requirements for your truck, but that you would not use radial tires because of erratic wear patterns. For your Information, I have enclosed a booklet published by the Rubber Manufacturers Association setting forth information on the care and service of radial and non-radial truck tires. On page 11 of this booklet there is a description of the irregular wear to which you refer, as well as instructions on how to prevent irregular wear from lessening the overall mileage the tire will give you. Hence, if you wish to use radial tires on your truck, there is no reason to expect them to perform unsatisfactory.; More significant, however, is the misunderstanding you have i suggesting that no bias ply tire is manufactured which would not have been overloaded on your truck. Such a tire is now manufactured and has been manufactured for at least the past 20 years. On page 30 of the enclosed booklet, you will find a table showing the load-carrying capacity of bias ply tire sizes mounted on 15 degrees drop center rims. The tire size mounted on your truck, the 11-22.5, does indeed have a maximum load of 5,430 pounds if it is a load range F tire. However, a load range G tire of the same size has a maximum load of 6,040 pounds, and would not overload if used on your truck. This is the tire you should probably use on the front axle.; I am sorry to hear of your accident and hope that you have recovere from your injuries. Your complaint about the failure of the Uniroyal Delta tire has been recorded, and the agency will be alert to other indications of problems with this tire. To date, however, we do not have sufficient data indicating a safety problem to open a formal investigation.; I want to thank you for taking the time to express your concern abou motor vehicle safety. It is only through the efforts of concerned citizens such as yourself that we can ensure maximum safety for all users of the highway. If you have any further questions or concerns about this matter or any other aspect of highway safety, please do not hesitate to contact me.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam2971OpenMr. W. G. Milby, Manager, Engineering Services, Blue Bird Body Company, P.O. Box 937, Fort Valley, GA 31030; Mr. W. G. Milby Manager Engineering Services Blue Bird Body Company P.O. Box 937 Fort Valley GA 31030; Dear Mr. Milby: This responds to your February 1, 1979, letter asking whether any la or regulation prohibits the remanufacture of a school bus with an old chassis and a new body when the completed vehicle does not comply with the new safety standards.; As you are aware, the agency has stated many times that such remanufactured vehicle need only comply with the standards in effect on the date of manufacture of the chassis as long as the remanufacturing process conforms to the guidelines established in Part 571.7(e) of our regulations. The agency does not view the remanufacturing problem as significant, because a vehicle's chassis normally wears out before its body. The recycling of noncomplying buses will cease when the supply of used chassis manufactured prior to April 1, 1977, disappears.; Sincerely, Frank Berndt, Acting Chief Counsel |
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ID: aiam3663OpenMr. Anton (Tony) Ostermeier, 19240 S. Vermont Avenue, Gardena, CA 90248; Mr. Anton (Tony) Ostermeier 19240 S. Vermont Avenue Gardena CA 90248; Dear Mr. Ostermeier: Thank you for your letter of February 4, 1983, supplying the furthe information we requested on January 28.; The 1955 Mercedes replica which you contemplate building is a hybrid o new and old parts. The body is of your construction and consists of new parts. You fabricate the chassis using new tubing, however, its front cross member may be either a new replacement Mustang part (1974-1978 models) or one actually taken from a vehicle in use. Similarly, the front suspension, differential and rear suspension, and transmissions may be new replacement parts or taken from vehicles in use. You will employ used rear wheel cylinders in the braking system and used engines (either a 1964 Chrysler Slant 6 or a 1969 Chevrolet V-8). Any equipment that has previously been used will be rebuilt to the manufacturer's specifications, and new parts will be incorporated where necessary.; As a general rule, the agency has no requirements for 'used' vehicles Whether a vehicle is treated as new or used depends on the origin of its parts. For example, we regard an assemblage consisting of a new body on the chassis of a vehicle previously registered for use on the public roads as a 'used' motor vehicle and therefore not subject to the Federal motor vehicle standards. On the other hand, the agency will consider a truck newly manufactured when an old cab is replaced with a new one unless at least the engine, transmission, and drive axle of the assembled vehicle are not new and at least two of these components were taken from the same vehicle.; The vehicle you propose to manufacture is somewhat different fro either of these examples, but we have concluded that it is a 'new' motor vehicle and must comply with Federal motor vehicle safety standards applicable to new passenger cars. Not only do previously unused parts appear to predominate in your plans, but, in addition, the old parts that are used will be rebuilt with new parts where necessary, to the manufacturer's original specifications. With the exception of the 1964 engine, the rebuilt components were originally used in vehicles manufactured to meet the Federal motor vehicle safety standards and there appears no reason why your product may not also be manufactured to comply, even though it is a replica of a 1955 car.; Use of the 1964 engine could raise problems of compliance with Safet Standard No. 124, *Accelerator Control Systems*, and with Safety Standard No. 301, *Fuel System Integrity*. However, in that event, we believe that you (as a producer of less than 10,000 vehicles a year) would be eligible to apply for a temporary exemption from those standards, or any other standard where immediate compliance would cause you substantial economic hardship. I enclose an information sheet which tells you where you may obtain a copy of our regulations, including the standards and temporary exemption petition procedures.; If you have further questions, we would be happy to assist you. Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam3399OpenMarlin H. Dawdy, State Farm Mutual Automobile Insurance Co., Easter Office, 1500 State Farm Blvd., Charlottesville, VA 22909; Marlin H. Dawdy State Farm Mutual Automobile Insurance Co. Easter Office 1500 State Farm Blvd. Charlottesville VA 22909; Dear Mr. Dawdy: This is in response to your letter of April 17, 1981, asking whethe the Virginia Certificate of Title contains sufficient language in its odometer disclosure statement to serve as a substitute for the Federal Disclosure form.; The information on Virginia's revised title satisfies the requirement of the Federal odometer disclosure requirements and the title may be used in lieu of a separate form.; Sincerely, John Womack, Assistant Chief Counsel for General Law an Legislation; |
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ID: aiam4148OpenMr. Roland L. Lafleur, 1155 W. Grolee St., Opelousas, LA 70570; Mr. Roland L. Lafleur 1155 W. Grolee St. Opelousas LA 70570; Dear Mr. Lafleur: This is in reply to your letter of May 5, 1986, to our former Chie Counsel, Jeffrey Miller, asking about comparative costs of a center high-mounted stop lamp. You read that the cost of such a lamp was $4 to $7, but in fact it cost you $136.18, tax included, to have one installed on your 1984 Cadillac.; The figures of $4 to $7 represent the agency's conclusions as to th cost to a vehicle manufacturer to install the new lamp as standard equipment when its installation became mandatory for new vehicles. As the new requirement does not extend to aftermarket equipment such as the lamp you bought for your 1984 Cadillac, the agency's cost estimates should not be read as applying to it. Also, our estimate was for the 'average' vehicle. Costs will vary by manufacturer and by carline within a given manufacturers' (sic) fleet according to the particular design and placement chosen. In spite of your dissatisfaction over the cost you have nevertheless wisely equipped your car with a safety device which should lessen the likelihood of expensive rear end collisions and the injuries to passengers that can occur. We appreciate your interest in the lamp.; Sincerely, Erika Z. Jones, Chief Counsel |
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ID: aiam3377OpenMr. Ronald H. Wonders, Wisconsin State Patrol, District No. 1, Junction I-90 & Hwy. 151, 4845 E. Washington Avenue, Madison, WI 53704; Mr. Ronald H. Wonders Wisconsin State Patrol District No. 1 Junction I-90 & Hwy. 151 4845 E. Washington Avenue Madison WI 53704; Dear Mr. Wonders: This responds to your October 28, 1980, letter asking whether Standar No. 217, *Bus Window Retention and Release*, requires that there be an aisle to provide access to a side exit. The answer to your question is no.; Standard No. 217 states that side emergency exits on school buses mus have an opening of 45 by 24 inches. The standard further states that a vertical transverse plane tangent to the rear most point of a seat back shall pass through the forward edge of the emergency exit. These requirements mean only that the size of the opening must be 45 by 24 inches, and that the opening must be located in a specific place with reference to the seat back.; The Federal government does not require an aisle or other access to side emergency exit. Although some seats may partially block a side emergency exit, it can still be used for emergency exit purposes and is supplementary to a rear emergency exit. The agency adopted this approach to side emergency exits as a balance between the desire for additional exits in school buses and the need to maintain the fullest possible seating in school buses as well as the proper seat spacing.; A State is permitted to require an aisle leading to the side exit i the State determines that this is an area that it would like to regulate. Such a regulation would not be preempted, because the Federal government does not regulate the placement of aisles in buses. However, the required seat spacing would need to be retained. This means that the seat behind the aisle leading to a side emergency exit would need to have a restraining barrier placed in front of it. The net effect of the aisle and the restraining barrier could be a substantial loss of seating capacity.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam4518OpenMr. Amnon Shomlo President, A.A.S. 3364 Catamaran Way Jacksonville, FL 32217; Mr. Amnon Shomlo President A.A.S. 3364 Catamaran Way Jacksonville FL 32217; Dear Mr. Shomlo: This is in reply to your letter of March 25, 1988 enclosing a 'Peace' decal designed to be affixed to the center highmounted stop lamp. The letters and design are in white, printed on transparent plastic, 'in an effort to preserve the basic requirements for an effective projected luminous area of the lens and the specified candela.' You have asked what 'Federal/Legal authorizations we need to obtain, stating that we comply with all the regulations and the requirements regarding this product.' There are no regulations that apply directly to the decal, nor any Federal restrictions on its sale. Thus you cannot state in any sales materials that the product meets Federal requirements, for there are none. If a center highmounted brake lamp would continue to meet all applicable requirements of Motor Vehicle Safety Standard No. 108 after installation of your decal, there are no restrictions on its use. Although you intend the product to preserve the requirements of Federal Motor Vehicle Safety Standard No. 108, it is not certain that this will occur. The decal has the potential of obscuring light from some of the l3 test points at distances where candela photometrics must be measured and the specified minima met. However, its actual effect can be determined only through laboratory tests on lamps of different sizes and lens and reflector designs. Although you have no liability under Federal law for selling this decal, a violation of the National Traffic and Motor Vehicle Safety Act will result if the decal creates a noncompliance and if it is applied by a manufacturer, distributor, or dealer before the first sale of the vehicle. A violation will also occur if the decal creates a noncompliance and if it is applied after the vehicle's first sale by any of these persons or by a motor vehicle repair business. There is no violation of Federal law if the decal is applied by a person other than those named above, such as the vehicle owner. In the absence of a violation of Federal law there may nonetheless be State statutes restricting the application of the decal under any circumstances. We are unable to advise you on State laws. I hope that this answers your question. Sincerely, Erika Z. Jones Chief Counsel; |
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ID: aiam2835OpenMs. Janine M. Schulte, North Central Tank Repair, Box 300, Holdingford, MN 56340; Ms. Janine M. Schulte North Central Tank Repair Box 300 Holdingford MN 56340; Dear Ms. Schulte: This responds to your January 30, 1978, letter asking whether you ar permitted to mount temporarily a body on a vehicle when you know that the body is of a greater load carrying capacity than is appropriate for the vehicle's gross vehicle weight rating (GVWR). You indicate that some other manufacture would finish the mounting process and certify the vehicle for compliance with the Federal motor vehicle safety standards.; The National Highway Traffic Safety Administration (NHTSA) ha indicated on many occasions that vehicle overloading poses a serious safety problem for the affected vehicle, in particular, and the motoring public in general. Accordingly, the agency has stated its determination to hold manufacturers responsible for vehicles that they manufacture which will exceed their GVWR's when fully loaded with their intended cargo. The NHTSA considers such overloading to constitute a safety-related defect.; In the operation that you are considering, you would be considered a intermediate vehicle manufacturer. As such, you would be required to comply with all of the requirements in Part 568, *Vehicles Manufactured in Two or More Stages*, that apply to intermediate manufacturers. The NHTSA would consider you to be partially responsible for the construction of a vehicle that when loaded with its intended cargo will exceed its GVWR. Possible agency action might include a mandatory recall and remedy and civil penalties of up to $1,000 per vehicle.; Sincerely, Joseph J. Levin, Jr., Chief Counsel |
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ID: aiam0808OpenMr. W.J. Sears, Vice President, Rubber Manufacturers Association, 1346 Connecticut Avenue, N.W., Washington, D.C. 20036; Mr. W.J. Sears Vice President Rubber Manufacturers Association 1346 Connecticut Avenue N.W. Washington D.C. 20036; Dear Mr. Sears: This is in response to your letter of July 24, 1972, t Mike Peskoe, and your letter of July 25, 1972, to Lawrence Schneider. Your letter of July 24 discusses your dissatisfaction with the present method of amending the Appendices of Standards 109 and 110 and suggest that we meet to discuss with you possible methods of changing this procedure. We will be happy to meet with you to discuss possible other methods of amending the Tables, and if you will contact either Ed Wallace or Mike they will arrange a meeting with you.; In your letter of July 25 you request the legal status of a petitio dated July 4, 1972, from E.T.R.T.O., to amend the Tables of standard 109 and 110 to include a tire size designation and alternative rim sizes which have not been standardized by E.T.R.T.O. The guidelines for amending the Tables, which you cite in you letter, do not require tire size designations and alternative rims to be standardized by the respective associations before inclusion in the Tables. Rather, They require only that the petition indicate whether the tire size designation and rim sizes have been standardized. As a consequence, the size in question (250-15 Radial) and the alternative rim sizes were included in the amendment to the Tables published August 2, 1972 (37 F.R. 15430). If you object to the inclusion of the size designation in the Tables, as you have been informed by phone, your objection with supporting statements should be submitted to NHTSA in writing, within 30 days from publication of the amendment to the Tables.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam3727OpenMr. Buck Burwell, Vice President, Merchant's, Inc., 9073 Euclid Ave., Manassas, VA 22110; Mr. Buck Burwell Vice President Merchant's Inc. 9073 Euclid Ave. Manassas VA 22110; Dear Mr. Burwell: This responds to your recent letter to Mr. Kratzke of my staff, askin questions about a group of trucks tires you wish to sell. Specifically, your company received a large shipment of truck tires from Tong Shinn Chemical Company in Korea. Some of those tires did not have the D.O.T. symbol and other information labelled on the sidewall, as required for all new truck tires by Safety Standard No. 119, *New pneumatic tires for motor vehicles other than passenger cars (49 CFR S571.119). Your company tried to return the tires to the Korean manufacturer, because tires which do not meet the requirements of Standard No. 119 may not be legally sold in this country. However, the Korean manufacturer has gone out of business, leaving your company with $15,000 worth of tires which may not be sold legally in this country unless appropriate information is labelled on the sidewalls.; You indicated in your letter that you would be willing to label th appropriate information onto the sidewalls of the tires. Tong Shinn has indicated that those tires are of the same quality as the tires it shipped to you with the DOT markings. Further, you indicated that your company would be willing to store the names and addresses of the purchasers of these tires, in the event a safety-related recall is necessary. After considering these facts and representations, I believe you may label the tires with the necessary information and sell them, provided that you get some more information from the Korean manufacturer.; This agency has previously allowed the marking of truck tires by party other than the manufacturer in only one instance. That case, which also involved imported truck tires, included four factors which led the agency to make an exception to the policy that only a tire manufacturer can label the necessary information on the sidewall of the tires. Those factors were:; >>>(1) The manufacturer certified that the unmarked tires met th requirements of Standard No. 119, except for the labelling requirement,; (2) The manufacturer provided the appropriate information to b labelled on the tires,; (3) The manufacturer agreed to be responsible for the tires in th event of a safety-related recall, and; (4) The manufacturer agreed that the marking method to be used by th importer would not weaken the tires and destroy their compliance with Standard No. 119.<<<; In this case, Tong Shinn has already provided the first item liste above. It will be necessary for you to contact Tong Shinn to learn what information should be labelled on the tires for purposes of section S6.5 of Standard No. 119 (copy enclosed) and also the appropriate codes and information for the tire identification number, which must be labelled on the sidewalls of the tires per 49 CFR 574, *Tire Identification and Recordkeeping* (copy enclosed). Please furnish Mr. Kratzke with a copy of the information you receive from Tong Shinn on this subject.; As to the third item above, you indicate that your company would b willing to be responsible for the tires in the event of a safety- related recall. To do so, it will be necessary for your company to record the names and addresses of the purchasers of these tires, and store that information for a three year period. For further information on the responsibilities you will have to undertake, see section 574.7 for tire registration requirements for tire manufacturers.; It will also be necessary for you to contact Tong Shinn and explain ho you propose to mark the information of the sidewalls of these tires, and get them to agree that this method of marking the tires will not affect their compliance with Standard No. 119. Again, please furnish a copy of that agreement to Mr. Kratzke of this office.; After you have received this additional information, this agency has n objection to your company marking the tires and selling them. Please understand that this is permitted only because of the unique circumstances of this particular situation, and that if the Korean manufacturer had not gone out of business, you would not be allowed to mark these tires. However, in these circumstances, some flexibility in the requirements is necessary to help you avert a financial loss, while maintaining the necessary safety assurances for purchasers of these tires. If you have any further questions or need additional information, please contact Mr. Steve Kratzke of my staff at (202) 426- 2992.; Sincerely, Frank Berndt, Chief Counsel |
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Request an Interpretation
You may email your request to Interpretations.NHTSA@dot.gov or send your request in hard copy to:
The Chief Counsel
National Highway Traffic Safety Administration, W41-326
U.S. Department of Transportation
1200 New Jersey Avenue SE
Washington, DC 20590
If you want to talk to someone at NHTSA about what a request for interpretation should include, call the Office of the Chief Counsel at 202-366-2992.
Please note that NHTSA’s response will be made available in this online database, and that the incoming interpretation request may also be made publicly available.